NASHUA - Best friends since high school, Joseph Lamoureux and Jared Antista have taken their love of sports and developed a company that provides customers a sneak peek into the workouts of professional athletes.

Go Pro Workouts is a Nashua-based startup developed by six former high school and college athletes. It offers clients sport-specific training routines used by such elite athletes as world champion skier Hannah Kearney, NFL running back Jamaal Charles and NBA center Roy Hibbert.

"There are a lot of sports companies out there that make the shoes you wear and the products you use. They claim that they make you run faster and jump higher," said Antista, 33. "We feel that our product and the fitness training information we provide is something that can actually make an athlete better."

Go Pro Workouts is an online program where customers can input, track, share and save all of their workout progress. Each $99 program features a professional athlete, in video form, who walks the customer through each exercise in an eight-week session, with typical workouts lasting about 1 or 1½ hours.

The exercise programs cover cardio, speed, agility and strength training, and can be accessed via a mobile Web app that allows clients to bring their phone or iPad to the gym to access content.

"It really is hard work and access to the right training information that will make you better. It is a combination of the two," said Lamoureux, explaining Go Pro Workouts offers expertise from professional athletes willing to help and motivate other athletes to become the best that they can be at their individual sports.

The company recently signed a contract with Will Middlebrooks of the Boston Red Sox, the first professional baseball player to join the Go Pro Workouts roster. Some of the other athletes include USA soccer defender Christie Rampone, NFL linebacker Von Miller, Major League Lacrosse defenseman Kyle Hartzell, USA volleyball opposite Destinee Hooker and NBA dancer Morgan Laskey, among others.

More than 20 professional athletes have agreed to share their secret workout tips with Go Pro Workout customers, each of them focusing on sport-specific skills.

"I think I am most thrilled that we are doing a shoot with a Red Sox player - someone who is local for us, although I am really happy about all of the athletes we have signed on," Lamoureux said.

Lacrosse and football have become two of the most popular sports by Go Pro Workout clients, according to Antista, who said the program is geared toward all age levels and abilities, but seems to attract many high school and college athletes.

The company previously rolled out a free seven-day trial that attracted more than 3,000 people to pilot the athletic programs. Since then, organizers have tweaked some of the features in preparation for major marketing efforts in the coming months.

"Our end goal is to be a leader in the industry, and to become the number one go-to resource covering every sport for males and females," Antista said.

Go Pro Workouts has received startup funding in two separate rounds from private investors. It plans on using the capital towards several initiatives, including the addition of more professional athletes, and the development of a line of customized, sport-specific nutrition planning products.

Furthermore, GNC.com is selling the workout programs on its own website, and the company is in discussions with some large sporting good retail chains hoping to gain even more support.

While Lamoureux and Antista are the only company representatives who live in New Hampshire, the Go Pro Workouts team also consists of four other partners: Kevin Asplund for product development, Jeff Seals for Web development, Jordan Valente for videography and Rob Hammer for photography.

Team members have the unique opportunity of meeting each professional athlete for individual video shoots.

"We were a little nervous when we first started doing this, but we have learned that many of the athletes are such good people," Antista said. "The people we are working with are phenomenal, and many of them are doing this with royalty deals only."

Antista declined to elaborate on how much money in royalty fees the athletes are receiving, nor would he comment on how much money is being given upfront when select clients sign contracts with the company.

"Last year was a building year for us, but this year we are really going to focus on our marketing," said Lamoureux, who is confident about the company's future.

Antista agrees, saying sales are increasing every month. Starting this month, each team member will begin working full-time for the company, trying to accelerate sales and increase opportunities.